complete drainage report rev 9

POA-1 2024-05-12 HydroCad - Proposed POA 1B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 119 Summary for Pond 18P: Basin 5 Inflow Area = 46,608 sf, 92.62% Impervious, Inflow Depth = 8.21" for 100-Year event Inflow = 9.58 cfs @ 12.10 hrs, Volume= 31,871 cf Outflow = 6.04 cfs @ 12.13 hrs, Volume= 31,871 cf, Atten= 37%, Lag= 1.7 min Discarded = 1.37 cfs @ 11.57 hrs, Volume= 26,452 cf Primary = 4.67 cfs @ 12.13 hrs, Volume= 5,419 cf Routed to Pond 16P : Basin 1 Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 579.76' @ 12.13 hrs Surf.Area= 14,810 sf Storage= 4,513 cf Plug-Flow detention time= 8.7 min calculated for 31,867 cf (100% of inflow) Center-of-Mass det. time= 8.7 min ( 749.8 - 741.1 ) Volume #1 Invert 579.00' Elevation (feet) 579.00 580.00 581.00 582.00 583.00 584.00 584.30 Device #1 #2 Avail.Storage 31,397 cf Surf.Area (sq-ft) 14,810 14,810 14,810 14,810 14,810 14,810 14,810 Routing Primary Discarded Invert 579.25' 579.00' Storage Description Custom Stage Data (Prismatic) Listed below 78,493 cf Overall x 40.0% Voids Inc.Store (cubic-feet) 0 14,810 14,810 14,810 14,810 14,810 4,443 Cum.Store (cubic-feet) 0 14,810 29,620 44,430 59,240 74,050 78,493 Outlet Devices 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 4.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=1.37 cfs @ 11.57 hrs HW=579.05' (Free Discharge) 2=Exfiltration (Exfiltration Controls 1.37 cfs) Primary OutFlow Max=4.66 cfs @ 12.13 hrs HW=579.76' (Free Discharge) 1=Sharp-Crested Rectangular Weir (Weir Controls 4.66 cfs @ 2.34 fps) Pond 18P: Basin 5 Sharp-Crested Rectangular Exfiltration Weir